Grease gun



April 27,I J. w, cRoLLlE GREASE GUN Filed 0G11. 17, 1941 INVENTOR J0/1'N W/LL/AM CLL/E Patented Apr. 27, 1943 GREASE GUN John william crouie, Dagenham, England, as-

signor to Ilse Zimt, New York, N. Y.

Application October 17, 1941, Serial No. 415,370 In Great Britain July 8, 1941 4 Claims. (Cl. 221547.14)

Y This invention is for improvements in or relatingtogrease guns and more particularly to handoperated lubricating guns of Jthe type in which lubricant lis forced under pressure from a low pressure storage chamber in which the lubricant is maintained under pressure in excess of atmospheric pressure. by means of a plunger, into a high pressure cylinder from which the lubricant is expelled during a working stroke by means of aram, and the present invention has ior one of its objects the provision of means whereby the ram hitherto employed upon grease guns of the above. character may be locked in the forward position thereof in a more eicient manner than hitherto.

, Another object of the present invention is to provide a ram which is considerably strengthened at least at that part thereof whichextends externally of the gun When the ram is in its released position.

A further object of the present invention is to provide a ram consisting of at least two portions, one of larger cross-section thanthe portion operating as the ram, for "the purpose hereinafter specied.

' The foregoing objects and other objects, features andadvantages of the invention will be` more clearly set forth or will become evident from the Afollowing specification in which the details and principles of the invention are disclosed.

Inthe ldrawing which illustrates an exemplary form of the invention and which forms the basis for the specification:

Fig. 1 illustrates in sectional elevation a lubricating gun constructed according to the present invention;

Fig. 2 illustrates a portion of the ram with a locking pin extending therethrough;

Fig. 3 illustrates a portion of a screw threaded shaft which carries the plunger of the low pressure storage chamber;

Fig. 4 illustrates in perspective the inner member of a sleeve employed in connection with the invention;

Fig. 5 is a sectional plan View of the inner member taken on line 5-5 of Fig. 4;

Fig. 6 illustrates in perspective the outer member of said sleeve;

Fig. 7 shows an elevational view of the ram proper.

Referring to the drawing, there is illustrated in Fig. 1 a lubricating gun of the type specified and disclosed in detail in U. S. Patent application Serial No. 393,605, filed May 15, 1941, in which a ram I extends through a screw-threaded use.

shaft v2 which engages a plunger 3 of the low pressure chamber 4. The operation of the lubrieating gun is, that, upon the manipulation of the spindle or shaft 2 (through handle connection) theforwardmovement of plunger 3 in the low pressure chamber 4 is eifectuated, so that the lubricant placed in said chamber 4, is forced into a high pressure cylinder, forming a tubular prolongation of said low pressure chamber 4, as seen in the lower part of Figure 1. The forward part ofjthe ram I snugly ts in said prolongation and is adapted to exert a high pressure upon the lubricant or grease previously forced into said tubular prolongation. In accordance with the present invention the ram I is preferably constructed at that end thereof remote from where it exerts pressure upon the grease, with a portion 5 which is of larger diameter than the diameter of the ram l proper, thus providing strength to at least that operating portion of the ram which normally extends beyond the end of the screwthreaded shaft 2 when the ram is in its retracted position, thus ensuring that the ram is not easily bent should it be accidentally dropped during Preferably the ram is built up of two portions, one portion 5 provided with a screw-threaded bore 20 into which the screw-threaded end of the ram I extends. The hole in the screwthreadedshaft 2 through which the ram extends is preferably, from the point of View of ease of manufacture, made of the same diameter throughout, but is screw-threaded at the end 6 which receives the ram I with a nipple 'I having a hole large enough to receive the ram.

A grease gun of the type hereinbefore specified, is constructed according to the present invention so that when the gun is out of use the ram extends as far into the gun proper as is possible, and for this purpose means are provided whereby the ram is held in its forward position against the action of a spring 8 normally tending to hold the ram in the retracted position. According to the present invention, there extends around the screw-threaded shaft 2 of the low pressure chamber 4 a sleeve built up of inner and outer members. The inner member 9 (Figs. 4 and 5) is provided with a longitudinal slot I0 having a lateral extension II into which extends a pin I2 which passes diametrically through the upper portion 5 of the ram through a longitudinal slot I3 (Fig. 3) in the screw-threaded shaft 2 of the low pressure chamber 4 so that, as can be easily realized, when the ram is pressed into the gun and is given a quarter turn the pin I2 extending from the ram engages with the lateral extension Il of the longitudinal slot l in the inner member 9 of the sleeve and is held in the forward position. 'Ihe sleeve is preferably built up of two members, one comprising the inner liner 9 having an L-shaped slot formed therein, and an outer protecting member I4 (Fig. 6) provided with a knurled portion Illa, and the two members are preferably spot-welded together. The locking device hereinbefore described is simple in construction and easy to manipulate.

While there has been shown and described and pointed out the fundamental novel features of the invention as applied to the above embodiment, it will be understood that various admissions and substitutions and changes in the form and details of the apparatus illustrated and its operation may be made by those skilled in the art Without departing from the spirit of the invention.

Having thus described the invention what is claimed as new and desired to be secured by Letters Patent is:

1. In a grease gun device, in which lubricant may be forced successively from a low pressure cylinder into a high pressure cylinder, from which said lubricant may be'expelled by means of a ram passing through handle and shaft carrying the piston for said low pressure cylinder; a projection on said ram, and a sleeve provided with an inner slot and rotatably mounted between said low pressure cylinder and said handle, said sleeve being spacedly arranged from and placed around a portion of said ram adjacent said projection, said projection being engageable withsaid sleeve slot to guide said ram along said sleeve, said sleeve being provided with means upon movement of said ram into its forward position to lock said ram in said position by rotational movement of said sleeve relatively to said ram projection.

2. In a grease gun device, in which lubricant may be forced successively from a low pressure cylinder into a high pressure cylinder, from which said lubricant may be expelled by means of a ram passing through handle and shaft carrying the piston for said low pressure cylinder; a projection on said ram, and a sleeve rotatably mount-y ed between said low pressure cylinder and said handle and having an inner lining provided with an L-shaped slot, said sleeve being spacedly arranged from and placed around a portion of said ram adjacent said projection, said projection being engageable with said sleeve slot to guide said ram along said sleeve, said sleeve being adapted upon movement of said ram into its forward position to lock said ram in said position by rotational movement of said sleeve relatively to said ram projection.

3. In a grease gun device, in which lubricant may be forced successively from a low pressure cylinder into a high pressure cylinder, from which said lubricant may be expelled by means of a ram passing through handle and'shaft carrying the piston for said low pressure cylinder; a projection carried by said ram, a sleeve rotatably mounted between said handle and said low pressure cylinder, a lining connected to said sleeve and provided with a longitudinal slot having a lateral extension at one of its ends, said sleeve being spacedly arranged from and placed around a portion of said ram adjacent said projection, said projection being engageable with said longitudinal slot of said sleeve to guide said ram along said sleeve, said sleeve being adapted to engage with the longitudinal extension of the slot, said projection upon forward movement of said ram into its foremost position and upon rotational movement of said sleeve, being engageable with said lateral extension of said slot whereby saidv ram is retained in said foremost position.

4. In a grease gun device, in which lubricant may be forced successively from a low pressure cylinder into a high pressure cylinder, from Iwhich said lubricant may be expelled -by means of a ramfpassing through handle and shaft carrying the piston for said low pressure cylinder; a forward portion and a rearward portion provided at said ram, said rearward portion being adapted to interchangeably receive said forward portion of said ram, said rearward portion being provided with a projection, and a sleeve provided with an inner slot and rotatably mounted between said low pressure cylinder and said handle, said sleeve being spacedly arranged from and placed around a portion of said'ram adjacent said projection, said projection being engageable with saidsleeve slotl to guide said ram along said sleeve, said sleeve being provided with means upon movement of said ram into its forward position to lock said ram in said position -by rotational mpvement of said sleeve relativelyto said ram projection.

JOHN WILLIAM CROLLIE. 

